Sound-insulated building



Oct. 14,1930. 8. E. BALDUF SOUND INSULATED BUILDING 2 Sheets-Sheet 1Filed Aug. 6, 1928 INVENTOR Bra/20 E BczZduf W13 ATTORNE- Fig 2 Oct. 14,1930. B. E. BALDUF 1,773,412

SOUND INSULATED BUILDING Filed Aug. 6, 13 28 2 Sheets-Sheet 2 INVEN TOR.

.3712 no 5 Balduf 30 F 5 BY 2 Q 7 79 'ATTo fiEY Patented Oct.

UNITED STATES PATENT OFFICE BRUNO E. BALDUF, OF CHIOAGO, ILLINOIS,ASSIGNOB 130- UNITED STATES GYPSUM COMPANY, OF CHICAGO, ILLINOIS, A.CORPORATION OF ILLINOIS SOUND-INSULATED BUILDING Application filedAugust 6, 1928. Serial No. 287,614.

This inventionrelates to means for preventing the transfer of soundsfrom one'room to another and has reference more particularly to a wall,ceiling and floor construction in which comparatively light weight panelmembers are resiliently s aced apart from heavier wall members to a sorbthe force of sound waves in a room and prevent theirtransfertoanotherroom. The invention further relates to a combination ofthe resilient means for breaking the impact of impinging sound waves anda flocculent filler for making the sound insulation more eflicient.

In a composite wall made up of panels separated by air spaces, soundpasses from one room to another in any one of the following ways:

1. Air borne sounds in which sound waves strike the solid bodies formingthe walls, set these bodies into vibration and these bodies in turn, setup 'sound waves on the opposite side.

2. Transmission of impact'sound through vibration of the molecularstructure of the materials forming the wall bodies and the connectionsupports between the wall panels.

3. Drum action in the hollow spaces-of the wall in which sound wavesecho and reecho by reflection from the inner faces of the wall members,and thus amplify the sounds.

I have found that with walls of ordinary construction, sounds of certainfrequencies or pitch are transmitted through the wall more easily thanwith sounds of other frequencies or pitch. Thus, sounds'of certainfrequencies produce vibration of the materials forming the wall, andthis frequency is called a point of resonance. These points of resonanceare determined experimentally by operating an organ inside of a confinedroom and noting the ease with which the sound travels through the wallswhen difierent tones are played on the organ.

With my improved construction, a composite wall of two or more panels ormembers is formed, the members being separated by a resilient clip whichprevents the transmission of air borne sounds by dam ing or snubbing thevibration of the mem ers.

combination of structural features, I provide a wall construction whichhas an extremely high efficiency in the insulation of sound.

Some of the materials commonly used in sound insulation are; hair felt,vegetable fibers, quilts, etc. These materials have been found todecrease with age in their soundproofing qualities due to hardening,acking and carbonization of the fibers. also have the objection thatthey are not vermin proof nor fireproof.

An object of this invention, therefore, is to provide a wall structuremade up of two or more panels separated by flexible cli s having apermanent resiliency so that t e soundproofing efficiency will notdecrease with age.

Another object of the invention is to provide a composite wallconstruction of a plurality of panels in direct metallic contact byresilient clips which absorb the impact of impinging sound waves.

A further object of this invention is to provide a soundproof wallconstruction in which the points of resonance are eliminated through theuse ofa light, flo'cculent filling material; also to improve soundproofwall constructions in other respects hereinafter specified and claimed.a

Reference is to behad in accompanying drawings, forming a part of thisspecification, in which it is understood that the draw-- ings illustrateonly certain forms of the invention and in which,

Figure 1 is a fragmentary, sectional elevation of my improved soundinsulation.

Figure 2 is a perspective view of one of my hey showing the method ofattaching my resilient clips to a tile wall member.

Figure 5 is a fragmentary elevation of the device shown in Figure 4.

Figure 6 is a fragmentary, sectional elevation of my soundproof ceilingconstruction.

Figure 7 is a sectional View through the ceiling construction on theline 77 of Figure 6, and

Figure 8 is a fragmentary, sectional, plan View of a modified form ofthe device shown in Figure 4.

' Referring to the drawings by numerals, 10 indicates a heavy, masonryfloor or ceiling member or element, slab or panel and, 11 indicates asimilar masonry floor or ceiling member such as commonly separates oneroom from the room above in an apartment or oflice building, thesefloors preferably being made in the usual waiy of reinforced con crete,wood or the like. ach floor is preferably divided into rooms bypartition tile 12, which are made of gypsum or other suitable materialand form a panel of heavy or massive construction. Subfloors 13 aresupported above and spaced apart from the floors 10 and 11, or abovewooden joists 14:, by means .of resilient and flexible spring clips 15.

the clips 15 are supported on a bracket 16, but when wooden floors 14are used, the spring clips 15 may be attached directly to the subfloorsby means of large headed nails 17 passing through slots 20 in the clips.

Brackets 16 are preferably made of flat steel with a raised or offsetsection 18 adapted to support the bottom of the semi-elliptical springclips 15, a bolt 19 passing through a slot 20, in the spring clip andthrough a similar slot in the offset section 18. A washer 20 of softflexible material, is preferable interposed between the bottom of theclip 15 and the offset section 18, so as to prevent squeaking duetovibration of the sub-floor 13 and clip 15. The semi-elliptical springclips 15 are preferably bent inwardly on their upstanding legs and thenupwardly to form shoulders 21 which are provided with a plurality ofholes 22 so that nails can be driven through said holes into a nailingstrip 23, the latter being ordinarily constructed of wood.

The nailing strips may also be fastened to saddles hung over theshoulder 21, or in any other suitable way. The brackets 16, may beattached to the masonry floors 10 by means of grout 24, suitableopenings 25 being provided in said brackets so as to provide a betterbond between the grout 24:, and the masonry floors 10 and 11. The springclips 15 are preferable made of spring metal such as steel, but mightalso be made of such materials as wood fiber, celluloid or othersuitable non-metallic materials. The springs 15 and 44 are of sufiicientresiliency to prevent transhen masonry floors 10 and 11 are employed,

"the partitions dividing mission of sound by impact but are of sufiiasshredded gypsum or a mixture ofshredded gypsum and vegetable fibers todecrease the density of the mixture.

A more complete disclosure of this filler material will be found in mycopending application Serial N 0. 107,797 filed May 8, 1926, now maturedto Patent No. 1,723,989 of which this application is a continuation inpart. I have found that a mixture of this nature which has a density of15 to 35 pounos per cubic foot and which will pass through a 50 meshscreen is most efiicient in sound in.

sulation and a mixture of gypsum and vegetable fiber is especiallyeffective because it is vermin and fireproof and does not lose itsefliciency upon ageing. This filling substance is ordinarilymanufactured by shredding up waste or scrap. wallboard so that thesurfacepaper composing the outer covering of the wallboard isdisintegrated into fiber and mixes with the gypsum to form a light,fluffy product. The character and density of this product can becontrolled by the type of grinding machinery used and the percentage offiber. In constructing my soundproof floors, I preferably but notnecessarily use a layer 27, of building paper which extends between thesubfloor 13 and nailing strip 23 and lies on top of the filling material26, so as to prevent such filling material from being dison the nailingstrip 23.

In my improved soundproof construction, a space into rooms isconstructed in a general way the same as the floors, with certainvariations. I preferably build my partitions of gypsum tile 12, whichmay be-of any desired construction or shape, it being understood thatthese partitions may also be of wood or other materials. Spaced apartfrom each face of the partition tile 12, I preferably provide a panel ofgypsum wallboard 29, of the standard'composition, this,

wallboard or, plasterboard serving as a base for a layer of plaster 30.A channel or furring strip 31 of any suitable shape, such as that shown,is provided adjacent the junction of two of the wall boards 29, whichmay preferably but with means such as integral lugs 32 which are bentupwardly between the wallboards 29 and then bent over pins 33 forsecuring the turbed until the subfloor 13 is nailed in place notnecessarily be provided wallboards to the channel strip 31. One of myimproved resilient clips or shock absorbers is then secured to thepartition tile 12 by means of a pair of staples 34 passing through theslot in said clip in opposite directions and being driven into said tile12. The outstanding flanges 21 of the clip 15 are inserted inside theflanges 35 of the channel strips 31 and a wire 36 or other suitablemeans may then be twisted around the channel strip 31 and clip 15 sothat the panels 29 and plaster 30 are securely but resiliently attachedto the partition tile 12. The space between the wallboard 29 andpartition tile 12 is then filled with the flocculent gypsum filler 26,

so as to aid in preventing sound from passing from one room to the othethrough partition 12.

In constructing the ceilings of my improved soundproof structure, Ipreferably support wallboard 29 and plaster 30 by a channel or furringstrip 31 similar to that used in the wall construction. This furringstrip 31 is secured to a second channel strip 37 by means of a wire 38.In order toresiliently attach the channel strip 37 to the floor orceiling -11, I provide a U-shaped bracket 39 which passes around thechannel strip 37, being provided at its upper end with perforations 40,through which passes a wire or rod 41, the latter being embedded at itsupper end in the masonry ceiling l1. Secured to the bottom 42 of theU-shaped bracket 39, as by rivets 43, is a semi-circular, flat springclip 44, the outer ends of which are bent or curved to receive andsupport the bottom flange 45 of the channel strip 37. The space betweenthe wallboard 29 and masonry ceiling 11 is then filled with severalinches of the flocculent gypsum filler 26. Thus the panels composed ofwallboard 29 and plaster 30 is free to vibrate under the impact orinfluence of the sound waves below and such vibrations are preventedfrom being transferred to the masonry 11 and room above by the spring orresilient clips 44 combined with the filler 26. In the same way thesound waves are prevented from passing through the partition 12 by thespring clips 15 and filler 26.

It should be understood that the efficiency of the flocculent gypsumfiller which I use in the walls, floors and ceilings of my improvedsoundproof construction, is very high, due to the low density of thegypsum filler and also due to the small size of the particles of whichit is composed. By surrounding the spring clips 15 and brackets 39 withthe filler, transfer of sound through the molecular structure of theclip 15, brackets 39 and wire 41 is prevented or largely absorbed by thegypsum fill. Furthermore, the gypsum fill prevents any drum action inthe enclosed spaces between the various panels, that is any echoes ofthe sound passing through the wallboard 29 are absorbed by the gypsumfiller. The

gypsum filler also has an absorbing action by contact with the panels,in dampmg the vibrations of the wallboard 29 under the infiuence ofsound waves impinging upon the plaster panel 30. In general, I havefound that the combination of the spring clip with the flocculent gypsumfiller serves to prevent any points of resonance and provides asoundproofing system of substantially equal efficiency for all pitchesor tones of sound and which will not decrease in efliciency with age.The filler itself is vermin and fireproof.

While the gypsum filler adds considerably to the efliciency of mysoundproof construction, it may be omitted, still providing excellentresults due to the resilient action of. the spring clips. Likewise thefiller itself has a substantial value as a sound absorbing agent withoutthe use of the spring clips. In the specification and claims, the termpanel is selected by applicant to denote broadly any fiat buildingmember such as walls, floors, and ceilings, whether movable or fixed.The term wall is used by applicant to denote any type of partitionforming rooms, whether fixed, or movable, such as doors.

I would state in conclusion that while the illustrated examplesconstitute a practical embodiment of my invention, I do not limit myselfstrictly to the details herein illustrated and described sincemanifestly the same can be considerably varied without departing fromthe spirit of the invention as defined in the appended claims.

Having thus described my invention I claim as new and desire to secureby Letters Patent:-

1. In a building construction, a pair of spaced, parallel buildingelements, spring clips connecting said elements, said clips being ofsufficient resiliency and number to prevent sound transmission throughsaid elements by impact of sound waves, and a flocculent fillingmaterial of low density between said elements.

In a building construction, a pair of flat structural elements inspaced, parallel relation and adapted to be used in walls and ceilingsof buildings, shock-absorbing spring clips connecting said elements,said clips belng of suflicient resiliency to prevent transmission ofsound through said elements and being suflicient in number to carrystructural loads, and a flocculent filling material between saidelements for preventing sound transmission by drum action.

3. A soundproof wall construction comprising a plurality of panelmembers spaced apart and attached together by metallic resilientmembers, and a flocculent filler of low density in the spec between saidpanels for preventing sound transfer from one panel to the next.

4. A soundproof structure comprising a plurality of panels, one of saidpanels being a massive construction and a second panel being a lighterconstruct-ion, spring means for resiliently attachin said light andmassive panels together so that sound waves caus ing the vibration ofthe light panel will not cause the vibration of the heavy panel, and aflocculent filler of low density in the space between said panelsadapted to damp the vibrations of said s rings and light panels.

5. A soundproo structure comprising a plurality of panels, havingdifferent thickness, resilient spring clips adapted to secure saidpanels together in spaced, parallel relameans adapted to resilientlyattach said tion, and a flocculent gypsum filler'in the space betweensaid panels, said filler having a density of-1535 lbs-.per cubic foot.

. 6. A soundproof construction comprising a support member, a fiat,metallic spring of high flexibility secured to said support member, apanel secured to said sup ort member, a second panel secured to S2115)spaced apart from said first panel thereby, and a flocculent filler oflow density surrounding said spring in the space between said panelsadapted to prevent sound from being transferred from one panel to theotherthrough the molecular structure of said pariels to said slab andprevent transmission ofsound to said slab by impact, and a flocculentfiller between said panels and slab,"

said filler having a density of substantially I 15 lbs. per cubic foot.

- 9. A- soundproof structure comprising a wallboard panel, an attachingstrip attached to said panel, a second panel of massive con- Istruction, a spring clip adapted to resiliently connect said attaching.strip and said wallboard to said second panel so as to prevent soundtransmission to said second panel by impact, and a flocculent filler ofsubstantially 15. lbs. per cubic foot density between said wallboard andsaid second panel.

10. In a soundproof structure, a spring clip of flat metal bent intosemi-elliptical form and having outstanding arms, a light weight panelsecured to said arms, a heavier panel secured to the' body of the clip,and a flocculent filler of low density surrounding said spring.

relation to said wall member, an

' spring and 11. In a sound insulating structure a spring clipforreventin pact, a I) clip, a washer between said bracket an clipadaptedto prevent squeaking when said sprin is vibrated, a masonry slabsupporting said racket, a panel secured to said clip,

said panel.

12. In a building construction, a flat structural rigidly held wallmember, a plasterboard panel in spaced substantially arallel panelhaving an exteriorsurface coating of-cementitious material adapted toreceive impinging sound waves, and a series of highlyresilientconnectors intermediate saidpanel and said wall member, said connectorsbeing adapted to' decrease initial vibrations of either said wall memberor said panel due solely to impinging sound waves.

13. A soundproof wall construction comprising a vertical wall of massiveconstruction, a plurality of highly resilient clips attached to saidwall, and a panel of hghter construction having non-metallic componentsand secured to said spring clips in spaced, parallel relation to saidwall, said panel being adapted to be exposed to impinging sound waves,the sound vibration of said panel bein absorbed by said resilient clipsso that su stantially no sound passes through said wall.

sound transmission by imracket or supporting said s ring and aflocculent filler between said slab and 14. In a soundproof structure, aplurality of vertically extending building panels, said panelscomprising a central supporting panel of substantially rigidconstruction with a sound impact panel in spaced parallel relation toeach face of said central panel, and a plurality of inherently highlyresilient connectors between said panels adapted to absorb the impact ofsound waves impingin on the outer of said panels and substantiallyprevent the sound from being transferred through said structure. I t

15. A- wall structure comprising a framing, a wall panel associated withthe framing, spaced, narrow metallic spring clips carried by saidframing and connected to said panel, each of said spacers including ahighly resilient portion for receiving the sound impact vibrations andpreventing their transmission through said wall structure.

16. In a soundproof building structure, a pair of flat structuralelements in spaced,

parallel relation and adapted for use in walls and ceilings ofbuildings, one-ofsaid ele ments being of rigid construction and thesecond of said elements being substantially movable, said elements beingof continuous extent across the face of the building, and

inherently highly resilient shock absorbing sprin clips connecting saidelements so as to en stantially eliminate sound transmission throughsaid structure.

17. A soundproof Wall consisting of a plurality of spaced supports, apanel carried by the supports, metallic spring clip spacers carried bythe supports and including highly resilient portions for receiving thesound impact vibrations and preventing their transmission through saidwell.

BRUNO E. BALDUF.

